Detection and quantification of protein and nucleic acids from individual cells is desirable, but difficult to achieve because of the minute amount of material present in a single cell. Further, unlike bulk samples, a single cell cannot be divided into portions to separately analyze protein and nucleic acid levels. Although single molecule detection techniques or mass spectrometry may provide methods for achieving single cell analysis, such methods are expensive. Recently, an assay, the Proximity Extension Assay (PEA) has been developed that is sensitive enough to detect picogram quantities of protein (see, e.g., Lundberg et al., Nucl. Acids Res. 2011 August; 39(15):e102; epub 2011 Jun. 6, incorporated by reference herein). In one approach, the PEA employs a pair of antibodies, each having a oligonucleotide attached to it. The oligonucleotides contain regions that complement one another. When the antibodies bind to a target protein, the oligonucleotides are in close enough proximity so that complementary regions from each oligonucleotide hybridize to one another. The addition of a DNA polymerase results in extension of the hybridized oligonucleotides. The extension products can then be detected or quantified.